[AZ-Observing] Re: Telrad stellar limit

AJ et al,

An interesting experiment would be to compare magnitude limits when 
switching from only one eye to both eyes when using a Telrad.  I always use 
both.  The eye that's looking through the Telrad suffers in two ways. 
First, there is some pupil constriction (only in that eye) due to the red 
light.  Second, since there doesn't seem to be any AR coating on my Telrad, 
so the 45 degree glass plate reflects about 10% of the light at each 
surface,  giving a 20% loss.  This is much more than the usual 4% at each 
surface for perpendicular incidence.  Does all this seem reasonable?

Paul 

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